In connectors as connecting components for electronic devices for consumer use and for vehicle use, Ni-plated copper material or Ni-plated copper alloy material are used in which base plating of Ni or the like is applied to the surface of brass or phosphor bronze materials and, if necessary, Sn or Sn alloy plating is further applied to the base plating. Hereinafter, the Ni-plated copper material or the Ni-plated copper alloy material are also referred to as a Ni-plated copper or copper alloy material.
As such Ni-plated copper or copper alloy materials, for example, Patent Literature 1 discloses an electrical contact material including a contact base material, a ground layer composed of Ni formed on the surface of the contact base material, and an Ag-Sn alloy layer formed on the surface of the ground layer. According to Patent Literature 1, an electrical contact material excellent in wear resistance, corrosion resistance and processability is described, and the electrical contact material is described to be able to be produced with an extremely low cost.